builtin/clone.c

   1 /*
   2  * Builtin "git clone"
   3  *
   4  * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
   5  *               2008 Daniel Barkalow <barkalow@iabervon.org>
   6  * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
   7  *
   8  * Clone a repository into a different directory that does not yet exist.
   9  */
  10
  11 #include "builtin.h"
  12 #include "config.h"
  13 #include "lockfile.h"
  14 #include "parse-options.h"
  15 #include "fetch-pack.h"
  16 #include "refs.h"
  17 #include "refspec.h"
  18 #include "object-store.h"
  19 #include "tree.h"
  20 #include "tree-walk.h"
  21 #include "unpack-trees.h"
  22 #include "transport.h"
  23 #include "strbuf.h"
  24 #include "dir.h"
  25 #include "sigchain.h"
  26 #include "branch.h"
  27 #include "remote.h"
  28 #include "run-command.h"
  29 #include "connected.h"
  30 #include "packfile.h"
  31 #include "list-objects-filter-options.h"
  32 #include "object-store.h"
  33
  34 /*
  35  * Overall FIXMEs:
  36  *  - respect DB_ENVIRONMENT for .git/objects.
  37  *
  38  * Implementation notes:
  39  *  - dropping use-separate-remote and no-separate-remote compatibility
  40  *
  41  */
  42 static const char * const builtin_clone_usage[] = {
  43         N_("git clone [<options>] [--] <repo> [<dir>]"),
  44         NULL
  45 };
  46
  47 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
  48 static int option_local = -1, option_no_hardlinks, option_shared;
  49 static int option_no_tags;
  50 static int option_shallow_submodules;
  51 static int deepen;
  52 static char *option_template, *option_depth, *option_since;
  53 static char *option_origin = NULL;
  54 static char *option_branch = NULL;
  55 static struct string_list option_not = STRING_LIST_INIT_NODUP;
  56 static const char *real_git_dir;
  57 static char *option_upload_pack = "git-upload-pack";
  58 static int option_verbosity;
  59 static int option_progress = -1;
  60 static enum transport_family family;
  61 static struct string_list option_config = STRING_LIST_INIT_NODUP;
  62 static struct string_list option_required_reference = STRING_LIST_INIT_NODUP;
  63 static struct string_list option_optional_reference = STRING_LIST_INIT_NODUP;
  64 static int option_dissociate;
  65 static int max_jobs = -1;
  66 static struct string_list option_recurse_submodules = STRING_LIST_INIT_NODUP;
  67 static struct list_objects_filter_options filter_options;
  68
  69 static int recurse_submodules_cb(const struct option *opt,
  70                                  const char *arg, int unset)
  71 {
  72         if (unset)
  73                 string_list_clear((struct string_list *)opt->value, 0);
  74         else if (arg)
  75                 string_list_append((struct string_list *)opt->value, arg);
  76         else
  77                 string_list_append((struct string_list *)opt->value,
  78                                    (const char *)opt->defval);
  79
  80         return 0;
  81 }
  82
  83 static struct option builtin_clone_options[] = {
  84         OPT__VERBOSITY(&option_verbosity),
  85         OPT_BOOL(0, "progress", &option_progress,
  86                  N_("force progress reporting")),
  87         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  88                  N_("don't create a checkout")),
  89         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  90         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  91                         N_("create a bare repository")),
  92         OPT_BOOL(0, "mirror", &option_mirror,
  93                  N_("create a mirror repository (implies bare)")),
  94         OPT_BOOL('l', "local", &option_local,
  95                 N_("to clone from a local repository")),
  96         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  97                     N_("don't use local hardlinks, always copy")),
  98         OPT_BOOL('s', "shared", &option_shared,
  99                     N_("setup as shared repository")),
 100         { OPTION_CALLBACK, 0, "recursive", &option_recurse_submodules,
 101           N_("pathspec"), N_("initialize submodules in the clone"),
 102           PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, recurse_submodules_cb,
 103           (intptr_t)"." },
 104         { OPTION_CALLBACK, 0, "recurse-submodules", &option_recurse_submodules,
 105           N_("pathspec"), N_("initialize submodules in the clone"),
 106           PARSE_OPT_OPTARG, recurse_submodules_cb, (intptr_t)"." },
 107         OPT_INTEGER('j', "jobs", &max_jobs,
 108                     N_("number of submodules cloned in parallel")),
 109         OPT_STRING(0, "template", &option_template, N_("template-directory"),
 110                    N_("directory from which templates will be used")),
 111         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
 112                         N_("reference repository")),
 113         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
 114                         N_("repo"), N_("reference repository")),
 115         OPT_BOOL(0, "dissociate", &option_dissociate,
 116                  N_("use --reference only while cloning")),
 117         OPT_STRING('o', "origin", &option_origin, N_("name"),
 118                    N_("use <name> instead of 'origin' to track upstream")),
 119         OPT_STRING('b', "branch", &option_branch, N_("branch"),
 120                    N_("checkout <branch> instead of the remote's HEAD")),
 121         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
 122                    N_("path to git-upload-pack on the remote")),
 123         OPT_STRING(0, "depth", &option_depth, N_("depth"),
 124                     N_("create a shallow clone of that depth")),
 125         OPT_STRING(0, "shallow-since", &option_since, N_("time"),
 126                     N_("create a shallow clone since a specific time")),
 127         OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
 128                         N_("deepen history of shallow clone, excluding rev")),
 129         OPT_BOOL(0, "single-branch", &option_single_branch,
 130                     N_("clone only one branch, HEAD or --branch")),
 131         OPT_BOOL(0, "no-tags", &option_no_tags,
 132                  N_("don't clone any tags, and make later fetches not to follow them")),
 133         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
 134                     N_("any cloned submodules will be shallow")),
 135         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
 136                    N_("separate git dir from working tree")),
 137         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 138                         N_("set config inside the new repository")),
 139         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 140                         TRANSPORT_FAMILY_IPV4),
 141         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
 142                         TRANSPORT_FAMILY_IPV6),
 143         OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
 144         OPT_END()
 145 };
 146
 147 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
 148 {
 149         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 150         static char *bundle_suffix[] = { ".bundle", "" };
 151         size_t baselen = path->len;
 152         struct stat st;
 153         int i;
 154
 155         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 156                 strbuf_setlen(path, baselen);
 157                 strbuf_addstr(path, suffix[i]);
 158                 if (stat(path->buf, &st))
 159                         continue;
 160                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
 161                         *is_bundle = 0;
 162                         return path->buf;
 163                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 164                         /* Is it a "gitfile"? */
 165                         char signature[8];
 166                         const char *dst;
 167                         int len, fd = open(path->buf, O_RDONLY);
 168                         if (fd < 0)
 169                                 continue;
 170                         len = read_in_full(fd, signature, 8);
 171                         close(fd);
 172                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 173                                 continue;
 174                         dst = read_gitfile(path->buf);
 175                         if (dst) {
 176                                 *is_bundle = 0;
 177                                 return dst;
 178                         }
 179                 }
 180         }
 181
 182         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 183                 strbuf_setlen(path, baselen);
 184                 strbuf_addstr(path, bundle_suffix[i]);
 185                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
 186                         *is_bundle = 1;
 187                         return path->buf;
 188                 }
 189         }
 190
 191         return NULL;
 192 }
 193
 194 static char *get_repo_path(const char *repo, int *is_bundle)
 195 {
 196         struct strbuf path = STRBUF_INIT;
 197         const char *raw;
 198         char *canon;
 199
 200         strbuf_addstr(&path, repo);
 201         raw = get_repo_path_1(&path, is_bundle);
 202         canon = raw ? absolute_pathdup(raw) : NULL;
 203         strbuf_release(&path);
 204         return canon;
 205 }
 206
 207 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 208 {
 209         const char *end = repo + strlen(repo), *start, *ptr;
 210         size_t len;
 211         char *dir;
 212
 213         /*
 214          * Skip scheme.
 215          */
 216         start = strstr(repo, "://");
 217         if (start == NULL)
 218                 start = repo;
 219         else
 220                 start += 3;
 221
 222         /*
 223          * Skip authentication data. The stripping does happen
 224          * greedily, such that we strip up to the last '@' inside
 225          * the host part.
 226          */
 227         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
 228                 if (*ptr == '@')
 229                         start = ptr + 1;
 230         }
 231
 232         /*
 233          * Strip trailing spaces, slashes and /.git
 234          */
 235         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 236                 end--;
 237         if (end - start > 5 && is_dir_sep(end[-5]) &&
 238             !strncmp(end - 4, ".git", 4)) {
 239                 end -= 5;
 240                 while (start < end && is_dir_sep(end[-1]))
 241                         end--;
 242         }
 243
 244         /*
 245          * Strip trailing port number if we've got only a
 246          * hostname (that is, there is no dir separator but a
 247          * colon). This check is required such that we do not
 248          * strip URI's like '/foo/bar:2222.git', which should
 249          * result in a dir '2222' being guessed due to backwards
 250          * compatibility.
 251          */
 252         if (memchr(start, '/', end - start) == NULL
 253             && memchr(start, ':', end - start) != NULL) {
 254                 ptr = end;
 255                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
 256                         ptr--;
 257                 if (start < ptr && ptr[-1] == ':')
 258                         end = ptr - 1;
 259         }
 260
 261         /*
 262          * Find last component. To remain backwards compatible we
 263          * also regard colons as path separators, such that
 264          * cloning a repository 'foo:bar.git' would result in a
 265          * directory 'bar' being guessed.
 266          */
 267         ptr = end;
 268         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
 269                 ptr--;
 270         start = ptr;
 271
 272         /*
 273          * Strip .{bundle,git}.
 274          */
 275         len = end - start;
 276         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
 277
 278         if (!len || (len == 1 && *start == '/'))
 279                 die(_("No directory name could be guessed.\n"
 280                       "Please specify a directory on the command line"));
 281
 282         if (is_bare)
 283                 dir = xstrfmt("%.*s.git", (int)len, start);
 284         else
 285                 dir = xstrndup(start, len);
 286         /*
 287          * Replace sequences of 'control' characters and whitespace
 288          * with one ascii space, remove leading and trailing spaces.
 289          */
 290         if (*dir) {
 291                 char *out = dir;
 292                 int prev_space = 1 /* strip leading whitespace */;
 293                 for (end = dir; *end; ++end) {
 294                         char ch = *end;
 295                         if ((unsigned char)ch < '\x20')
 296                                 ch = '\x20';
 297                         if (isspace(ch)) {
 298                                 if (prev_space)
 299                                         continue;
 300                                 prev_space = 1;
 301                         } else
 302                                 prev_space = 0;
 303                         *out++ = ch;
 304                 }
 305                 *out = '\0';
 306                 if (out > dir && prev_space)
 307                         out[-1] = '\0';
 308         }
 309         return dir;
 310 }
 311
 312 static void strip_trailing_slashes(char *dir)
 313 {
 314         char *end = dir + strlen(dir);
 315
 316         while (dir < end - 1 && is_dir_sep(end[-1]))
 317                 end--;
 318         *end = '\0';
 319 }
 320
 321 static int add_one_reference(struct string_list_item *item, void *cb_data)
 322 {
 323         struct strbuf err = STRBUF_INIT;
 324         int *required = cb_data;
 325         char *ref_git = compute_alternate_path(item->string, &err);
 326
 327         if (!ref_git) {
 328                 if (*required)
 329                         die("%s", err.buf);
 330                 else
 331                         fprintf(stderr,
 332                                 _("info: Could not add alternate for '%s': %s\n"),
 333                                 item->string, err.buf);
 334         } else {
 335                 struct strbuf sb = STRBUF_INIT;
 336                 strbuf_addf(&sb, "%s/objects", ref_git);
 337                 add_to_alternates_file(sb.buf);
 338                 strbuf_release(&sb);
 339         }
 340
 341         strbuf_release(&err);
 342         free(ref_git);
 343         return 0;
 344 }
 345
 346 static void setup_reference(void)
 347 {
 348         int required = 1;
 349         for_each_string_list(&option_required_reference,
 350                              add_one_reference, &required);
 351         required = 0;
 352         for_each_string_list(&option_optional_reference,
 353                              add_one_reference, &required);
 354 }
 355
 356 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 357                             const char *src_repo)
 358 {
 359         /*
 360          * Read from the source objects/info/alternates file
 361          * and copy the entries to corresponding file in the
 362          * destination repository with add_to_alternates_file().
 363          * Both src and dst have "$path/objects/info/alternates".
 364          *
 365          * Instead of copying bit-for-bit from the original,
 366          * we need to append to existing one so that the already
 367          * created entry via "clone -s" is not lost, and also
 368          * to turn entries with paths relative to the original
 369          * absolute, so that they can be used in the new repository.
 370          */
 371         FILE *in = xfopen(src->buf, "r");
 372         struct strbuf line = STRBUF_INIT;
 373
 374         while (strbuf_getline(&line, in) != EOF) {
 375                 char *abs_path;
 376                 if (!line.len || line.buf[0] == '#')
 377                         continue;
 378                 if (is_absolute_path(line.buf)) {
 379                         add_to_alternates_file(line.buf);
 380                         continue;
 381                 }
 382                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 383                 if (!normalize_path_copy(abs_path, abs_path))
 384                         add_to_alternates_file(abs_path);
 385                 else
 386                         warning("skipping invalid relative alternate: %s/%s",
 387                                 src_repo, line.buf);
 388                 free(abs_path);
 389         }
 390         strbuf_release(&line);
 391         fclose(in);
 392 }
 393
 394 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 395                                    const char *src_repo, int src_baselen)
 396 {
 397         struct dirent *de;
 398         struct stat buf;
 399         int src_len, dest_len;
 400         DIR *dir;
 401
 402         dir = opendir(src->buf);
 403         if (!dir)
 404                 die_errno(_("failed to open '%s'"), src->buf);
 405
 406         if (mkdir(dest->buf, 0777)) {
 407                 if (errno != EEXIST)
 408                         die_errno(_("failed to create directory '%s'"), dest->buf);
 409                 else if (stat(dest->buf, &buf))
 410                         die_errno(_("failed to stat '%s'"), dest->buf);
 411                 else if (!S_ISDIR(buf.st_mode))
 412                         die(_("%s exists and is not a directory"), dest->buf);
 413         }
 414
 415         strbuf_addch(src, '/');
 416         src_len = src->len;
 417         strbuf_addch(dest, '/');
 418         dest_len = dest->len;
 419
 420         while ((de = readdir(dir)) != NULL) {
 421                 strbuf_setlen(src, src_len);
 422                 strbuf_addstr(src, de->d_name);
 423                 strbuf_setlen(dest, dest_len);
 424                 strbuf_addstr(dest, de->d_name);
 425                 if (stat(src->buf, &buf)) {
 426                         warning (_("failed to stat %s\n"), src->buf);
 427                         continue;
 428                 }
 429                 if (S_ISDIR(buf.st_mode)) {
 430                         if (de->d_name[0] != '.')
 431                                 copy_or_link_directory(src, dest,
 432                                                        src_repo, src_baselen);
 433                         continue;
 434                 }
 435
 436                 /* Files that cannot be copied bit-for-bit... */
 437                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 438                         copy_alternates(src, dest, src_repo);
 439                         continue;
 440                 }
 441
 442                 if (unlink(dest->buf) && errno != ENOENT)
 443                         die_errno(_("failed to unlink '%s'"), dest->buf);
 444                 if (!option_no_hardlinks) {
 445                         if (!link(src->buf, dest->buf))
 446                                 continue;
 447                         if (option_local > 0)
 448                                 die_errno(_("failed to create link '%s'"), dest->buf);
 449                         option_no_hardlinks = 1;
 450                 }
 451                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 452                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 453         }
 454         closedir(dir);
 455 }
 456
 457 static void clone_local(const char *src_repo, const char *dest_repo)
 458 {
 459         if (option_shared) {
 460                 struct strbuf alt = STRBUF_INIT;
 461                 get_common_dir(&alt, src_repo);
 462                 strbuf_addstr(&alt, "/objects");
 463                 add_to_alternates_file(alt.buf);
 464                 strbuf_release(&alt);
 465         } else {
 466                 struct strbuf src = STRBUF_INIT;
 467                 struct strbuf dest = STRBUF_INIT;
 468                 get_common_dir(&src, src_repo);
 469                 get_common_dir(&dest, dest_repo);
 470                 strbuf_addstr(&src, "/objects");
 471                 strbuf_addstr(&dest, "/objects");
 472                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 473                 strbuf_release(&src);
 474                 strbuf_release(&dest);
 475         }
 476
 477         if (0 <= option_verbosity)
 478                 fprintf(stderr, _("done.\n"));
 479 }
 480
 481 static const char *junk_work_tree;
 482 static int junk_work_tree_flags;
 483 static const char *junk_git_dir;
 484 static int junk_git_dir_flags;
 485 static enum {
 486         JUNK_LEAVE_NONE,
 487         JUNK_LEAVE_REPO,
 488         JUNK_LEAVE_ALL
 489 } junk_mode = JUNK_LEAVE_NONE;
 490
 491 static const char junk_leave_repo_msg[] =
 492 N_("Clone succeeded, but checkout failed.\n"
 493    "You can inspect what was checked out with 'git status'\n"
 494    "and retry the checkout with 'git checkout -f HEAD'\n");
 495
 496 static void remove_junk(void)
 497 {
 498         struct strbuf sb = STRBUF_INIT;
 499
 500         switch (junk_mode) {
 501         case JUNK_LEAVE_REPO:
 502                 warning("%s", _(junk_leave_repo_msg));
 503                 /* fall-through */
 504         case JUNK_LEAVE_ALL:
 505                 return;
 506         default:
 507                 /* proceed to removal */
 508                 break;
 509         }
 510
 511         if (junk_git_dir) {
 512                 strbuf_addstr(&sb, junk_git_dir);
 513                 remove_dir_recursively(&sb, junk_git_dir_flags);
 514                 strbuf_reset(&sb);
 515         }
 516         if (junk_work_tree) {
 517                 strbuf_addstr(&sb, junk_work_tree);
 518                 remove_dir_recursively(&sb, junk_work_tree_flags);
 519         }
 520         strbuf_release(&sb);
 521 }
 522
 523 static void remove_junk_on_signal(int signo)
 524 {
 525         remove_junk();
 526         sigchain_pop(signo);
 527         raise(signo);
 528 }
 529
 530 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 531 {
 532         struct ref *ref;
 533         struct strbuf head = STRBUF_INIT;
 534         strbuf_addstr(&head, "refs/heads/");
 535         strbuf_addstr(&head, branch);
 536         ref = find_ref_by_name(refs, head.buf);
 537         strbuf_release(&head);
 538
 539         if (ref)
 540                 return ref;
 541
 542         strbuf_addstr(&head, "refs/tags/");
 543         strbuf_addstr(&head, branch);
 544         ref = find_ref_by_name(refs, head.buf);
 545         strbuf_release(&head);
 546
 547         return ref;
 548 }
 549
 550 static struct ref *wanted_peer_refs(const struct ref *refs,
 551                 struct refspec_item *refspec)
 552 {
 553         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 554         struct ref *local_refs = head;
 555         struct ref **tail = head ? &head->next : &local_refs;
 556
 557         if (option_single_branch) {
 558                 struct ref *remote_head = NULL;
 559
 560                 if (!option_branch)
 561                         remote_head = guess_remote_head(head, refs, 0);
 562                 else {
 563                         local_refs = NULL;
 564                         tail = &local_refs;
 565                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 566                 }
 567
 568                 if (!remote_head && option_branch)
 569                         warning(_("Could not find remote branch %s to clone."),
 570                                 option_branch);
 571                 else {
 572                         get_fetch_map(remote_head, refspec, &tail, 0);
 573
 574                         /* if --branch=tag, pull the requested tag explicitly */
 575                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 576                 }
 577         } else
 578                 get_fetch_map(refs, refspec, &tail, 0);
 579
 580         if (!option_mirror && !option_single_branch && !option_no_tags)
 581                 get_fetch_map(refs, tag_refspec, &tail, 0);
 582
 583         return local_refs;
 584 }
 585
 586 static void write_remote_refs(const struct ref *local_refs)
 587 {
 588         const struct ref *r;
 589
 590         struct ref_transaction *t;
 591         struct strbuf err = STRBUF_INIT;
 592
 593         t = ref_transaction_begin(&err);
 594         if (!t)
 595                 die("%s", err.buf);
 596
 597         for (r = local_refs; r; r = r->next) {
 598                 if (!r->peer_ref)
 599                         continue;
 600                 if (ref_transaction_create(t, r->peer_ref->name, &r->old_oid,
 601                                            0, NULL, &err))
 602                         die("%s", err.buf);
 603         }
 604
 605         if (initial_ref_transaction_commit(t, &err))
 606                 die("%s", err.buf);
 607
 608         strbuf_release(&err);
 609         ref_transaction_free(t);
 610 }
 611
 612 static void write_followtags(const struct ref *refs, const char *msg)
 613 {
 614         const struct ref *ref;
 615         for (ref = refs; ref; ref = ref->next) {
 616                 if (!starts_with(ref->name, "refs/tags/"))
 617                         continue;
 618                 if (ends_with(ref->name, "^{}"))
 619                         continue;
 620                 if (!has_object_file(&ref->old_oid))
 621                         continue;
 622                 update_ref(msg, ref->name, &ref->old_oid, NULL, 0,
 623                            UPDATE_REFS_DIE_ON_ERR);
 624         }
 625 }
 626
 627 static int iterate_ref_map(void *cb_data, struct object_id *oid)
 628 {
 629         struct ref **rm = cb_data;
 630         struct ref *ref = *rm;
 631
 632         /*
 633          * Skip anything missing a peer_ref, which we are not
 634          * actually going to write a ref for.
 635          */
 636         while (ref && !ref->peer_ref)
 637                 ref = ref->next;
 638         /* Returning -1 notes "end of list" to the caller. */
 639         if (!ref)
 640                 return -1;
 641
 642         oidcpy(oid, &ref->old_oid);
 643         *rm = ref->next;
 644         return 0;
 645 }
 646
 647 static void update_remote_refs(const struct ref *refs,
 648                                const struct ref *mapped_refs,
 649                                const struct ref *remote_head_points_at,
 650                                const char *branch_top,
 651                                const char *msg,
 652                                struct transport *transport,
 653                                int check_connectivity)
 654 {
 655         const struct ref *rm = mapped_refs;
 656
 657         if (check_connectivity) {
 658                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
 659
 660                 opt.transport = transport;
 661                 opt.progress = transport->progress;
 662
 663                 if (check_connected(iterate_ref_map, &rm, &opt))
 664                         die(_("remote did not send all necessary objects"));
 665         }
 666
 667         if (refs) {
 668                 write_remote_refs(mapped_refs);
 669                 if (option_single_branch && !option_no_tags)
 670                         write_followtags(refs, msg);
 671         }
 672
 673         if (remote_head_points_at && !option_bare) {
 674                 struct strbuf head_ref = STRBUF_INIT;
 675                 strbuf_addstr(&head_ref, branch_top);
 676                 strbuf_addstr(&head_ref, "HEAD");
 677                 if (create_symref(head_ref.buf,
 678                                   remote_head_points_at->peer_ref->name,
 679                                   msg) < 0)
 680                         die(_("unable to update %s"), head_ref.buf);
 681                 strbuf_release(&head_ref);
 682         }
 683 }
 684
 685 static void update_head(const struct ref *our, const struct ref *remote,
 686                         const char *msg)
 687 {
 688         const char *head;
 689         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 690                 /* Local default branch link */
 691                 if (create_symref("HEAD", our->name, NULL) < 0)
 692                         die(_("unable to update HEAD"));
 693                 if (!option_bare) {
 694                         update_ref(msg, "HEAD", &our->old_oid, NULL, 0,
 695                                    UPDATE_REFS_DIE_ON_ERR);
 696                         install_branch_config(0, head, option_origin, our->name);
 697                 }
 698         } else if (our) {
 699                 struct commit *c = lookup_commit_reference(the_repository,
 700                                                            &our->old_oid);
 701                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 702                 update_ref(msg, "HEAD", &c->object.oid, NULL, REF_NO_DEREF,
 703                            UPDATE_REFS_DIE_ON_ERR);
 704         } else if (remote) {
 705                 /*
 706                  * We know remote HEAD points to a non-branch, or
 707                  * HEAD points to a branch but we don't know which one.
 708                  * Detach HEAD in all these cases.
 709                  */
 710                 update_ref(msg, "HEAD", &remote->old_oid, NULL, REF_NO_DEREF,
 711                            UPDATE_REFS_DIE_ON_ERR);
 712         }
 713 }
 714
 715 static int checkout(int submodule_progress)
 716 {
 717         struct object_id oid;
 718         char *head;
 719         struct lock_file lock_file = LOCK_INIT;
 720         struct unpack_trees_options opts;
 721         struct tree *tree;
 722         struct tree_desc t;
 723         int err = 0;
 724
 725         if (option_no_checkout)
 726                 return 0;
 727
 728         head = resolve_refdup("HEAD", RESOLVE_REF_READING, &oid, NULL);
 729         if (!head) {
 730                 warning(_("remote HEAD refers to nonexistent ref, "
 731                           "unable to checkout.\n"));
 732                 return 0;
 733         }
 734         if (!strcmp(head, "HEAD")) {
 735                 if (advice_detached_head)
 736                         detach_advice(oid_to_hex(&oid));
 737         } else {
 738                 if (!starts_with(head, "refs/heads/"))
 739                         die(_("HEAD not found below refs/heads!"));
 740         }
 741         free(head);
 742
 743         /* We need to be in the new work tree for the checkout */
 744         setup_work_tree();
 745
 746         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
 747
 748         memset(&opts, 0, sizeof opts);
 749         opts.update = 1;
 750         opts.merge = 1;
 751         opts.fn = oneway_merge;
 752         opts.verbose_update = (option_verbosity >= 0);
 753         opts.src_index = &the_index;
 754         opts.dst_index = &the_index;
 755
 756         tree = parse_tree_indirect(&oid);
 757         parse_tree(tree);
 758         init_tree_desc(&t, tree->buffer, tree->size);
 759         if (unpack_trees(1, &t, &opts) < 0)
 760                 die(_("unable to checkout working tree"));
 761
 762         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
 763                 die(_("unable to write new index file"));
 764
 765         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 766                            oid_to_hex(&oid), "1", NULL);
 767
 768         if (!err && (option_recurse_submodules.nr > 0)) {
 769                 struct argv_array args = ARGV_ARRAY_INIT;
 770                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
 771
 772                 if (option_shallow_submodules == 1)
 773                         argv_array_push(&args, "--depth=1");
 774
 775                 if (max_jobs != -1)
 776                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
 777
 778                 if (submodule_progress)
 779                         argv_array_push(&args, "--progress");
 780
 781                 if (option_verbosity < 0)
 782                         argv_array_push(&args, "--quiet");
 783
 784                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
 785                 argv_array_clear(&args);
 786         }
 787
 788         return err;
 789 }
 790
 791 static int write_one_config(const char *key, const char *value, void *data)
 792 {
 793         return git_config_set_multivar_gently(key,
 794                                               value ? value : "true",
 795                                               CONFIG_REGEX_NONE, 0);
 796 }
 797
 798 static void write_config(struct string_list *config)
 799 {
 800         int i;
 801
 802         for (i = 0; i < config->nr; i++) {
 803                 if (git_config_parse_parameter(config->items[i].string,
 804                                                write_one_config, NULL) < 0)
 805                         die(_("unable to write parameters to config file"));
 806         }
 807 }
 808
 809 static void write_refspec_config(const char *src_ref_prefix,
 810                 const struct ref *our_head_points_at,
 811                 const struct ref *remote_head_points_at,
 812                 struct strbuf *branch_top)
 813 {
 814         struct strbuf key = STRBUF_INIT;
 815         struct strbuf value = STRBUF_INIT;
 816
 817         if (option_mirror || !option_bare) {
 818                 if (option_single_branch && !option_mirror) {
 819                         if (option_branch) {
 820                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 821                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 822                                                 our_head_points_at->name);
 823                                 else
 824                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 825                                                 branch_top->buf, option_branch);
 826                         } else if (remote_head_points_at) {
 827                                 const char *head = remote_head_points_at->name;
 828                                 if (!skip_prefix(head, "refs/heads/", &head))
 829                                         BUG("remote HEAD points at non-head?");
 830
 831                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 832                                                 branch_top->buf, head);
 833                         }
 834                         /*
 835                          * otherwise, the next "git fetch" will
 836                          * simply fetch from HEAD without updating
 837                          * any remote-tracking branch, which is what
 838                          * we want.
 839                          */
 840                 } else {
 841                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 842                 }
 843                 /* Configure the remote */
 844                 if (value.len) {
 845                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 846                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 847                         strbuf_reset(&key);
 848
 849                         if (option_mirror) {
 850                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 851                                 git_config_set(key.buf, "true");
 852                                 strbuf_reset(&key);
 853                         }
 854                 }
 855         }
 856
 857         strbuf_release(&key);
 858         strbuf_release(&value);
 859 }
 860
 861 static void dissociate_from_references(void)
 862 {
 863         static const char* argv[] = { "repack", "-a", "-d", NULL };
 864         char *alternates = git_pathdup("objects/info/alternates");
 865
 866         if (!access(alternates, F_OK)) {
 867                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 868                         die(_("cannot repack to clean up"));
 869                 if (unlink(alternates) && errno != ENOENT)
 870                         die_errno(_("cannot unlink temporary alternates file"));
 871         }
 872         free(alternates);
 873 }
 874
 875 static int dir_exists(const char *path)
 876 {
 877         struct stat sb;
 878         return !stat(path, &sb);
 879 }
 880
 881 int cmd_clone(int argc, const char **argv, const char *prefix)
 882 {
 883         int is_bundle = 0, is_local;
 884         const char *repo_name, *repo, *work_tree, *git_dir;
 885         char *path, *dir;
 886         int dest_exists;
 887         const struct ref *refs, *remote_head;
 888         const struct ref *remote_head_points_at;
 889         const struct ref *our_head_points_at;
 890         struct ref *mapped_refs;
 891         const struct ref *ref;
 892         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 893         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 894         struct transport *transport = NULL;
 895         const char *src_ref_prefix = "refs/heads/";
 896         struct remote *remote;
 897         int err = 0, complete_refs_before_fetch = 1;
 898         int submodule_progress;
 899
 900         struct refspec rs = REFSPEC_INIT_FETCH;
 901         struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
 902
 903         fetch_if_missing = 0;
 904
 905         packet_trace_identity("clone");
 906         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 907                              builtin_clone_usage, 0);
 908
 909         if (argc > 2)
 910                 usage_msg_opt(_("Too many arguments."),
 911                         builtin_clone_usage, builtin_clone_options);
 912
 913         if (argc == 0)
 914                 usage_msg_opt(_("You must specify a repository to clone."),
 915                         builtin_clone_usage, builtin_clone_options);
 916
 917         if (option_depth || option_since || option_not.nr)
 918                 deepen = 1;
 919         if (option_single_branch == -1)
 920                 option_single_branch = deepen ? 1 : 0;
 921
 922         if (option_mirror)
 923                 option_bare = 1;
 924
 925         if (option_bare) {
 926                 if (option_origin)
 927                         die(_("--bare and --origin %s options are incompatible."),
 928                             option_origin);
 929                 if (real_git_dir)
 930                         die(_("--bare and --separate-git-dir are incompatible."));
 931                 option_no_checkout = 1;
 932         }
 933
 934         if (!option_origin)
 935                 option_origin = "origin";
 936
 937         repo_name = argv[0];
 938
 939         path = get_repo_path(repo_name, &is_bundle);
 940         if (path)
 941                 repo = absolute_pathdup(repo_name);
 942         else if (!strchr(repo_name, ':'))
 943                 die(_("repository '%s' does not exist"), repo_name);
 944         else
 945                 repo = repo_name;
 946
 947         /* no need to be strict, transport_set_option() will validate it again */
 948         if (option_depth && atoi(option_depth) < 1)
 949                 die(_("depth %s is not a positive number"), option_depth);
 950
 951         if (argc == 2)
 952                 dir = xstrdup(argv[1]);
 953         else
 954                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 955         strip_trailing_slashes(dir);
 956
 957         dest_exists = dir_exists(dir);
 958         if (dest_exists && !is_empty_dir(dir))
 959                 die(_("destination path '%s' already exists and is not "
 960                         "an empty directory."), dir);
 961
 962         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 963
 964         if (option_bare)
 965                 work_tree = NULL;
 966         else {
 967                 work_tree = getenv("GIT_WORK_TREE");
 968                 if (work_tree && dir_exists(work_tree))
 969                         die(_("working tree '%s' already exists."), work_tree);
 970         }
 971
 972         if (option_bare || work_tree)
 973                 git_dir = xstrdup(dir);
 974         else {
 975                 work_tree = dir;
 976                 git_dir = mkpathdup("%s/.git", dir);
 977         }
 978
 979         atexit(remove_junk);
 980         sigchain_push_common(remove_junk_on_signal);
 981
 982         if (!option_bare) {
 983                 if (safe_create_leading_directories_const(work_tree) < 0)
 984                         die_errno(_("could not create leading directories of '%s'"),
 985                                   work_tree);
 986                 if (dest_exists)
 987                         junk_work_tree_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 988                 else if (mkdir(work_tree, 0777))
 989                         die_errno(_("could not create work tree dir '%s'"),
 990                                   work_tree);
 991                 junk_work_tree = work_tree;
 992                 set_git_work_tree(work_tree);
 993         }
 994
 995         if (real_git_dir) {
 996                 if (dir_exists(real_git_dir))
 997                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 998                 junk_git_dir = real_git_dir;
 999         } else {
1000                 if (dest_exists)
1001                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
1002                 junk_git_dir = git_dir;
1003         }
1004         if (safe_create_leading_directories_const(git_dir) < 0)
1005                 die(_("could not create leading directories of '%s'"), git_dir);
1006
1007         if (0 <= option_verbosity) {
1008                 if (option_bare)
1009                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
1010                 else
1011                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
1012         }
1013
1014         if (option_recurse_submodules.nr > 0) {
1015                 struct string_list_item *item;
1016                 struct strbuf sb = STRBUF_INIT;
1017
1018                 /* remove duplicates */
1019                 string_list_sort(&option_recurse_submodules);
1020                 string_list_remove_duplicates(&option_recurse_submodules, 0);
1021
1022                 /*
1023                  * NEEDSWORK: In a multi-working-tree world, this needs to be
1024                  * set in the per-worktree config.
1025                  */
1026                 for_each_string_list_item(item, &option_recurse_submodules) {
1027                         strbuf_addf(&sb, "submodule.active=%s",
1028                                     item->string);
1029                         string_list_append(&option_config,
1030                                            strbuf_detach(&sb, NULL));
1031                 }
1032
1033                 if (option_required_reference.nr &&
1034                     option_optional_reference.nr)
1035                         die(_("clone --recursive is not compatible with "
1036                               "both --reference and --reference-if-able"));
1037                 else if (option_required_reference.nr) {
1038                         string_list_append(&option_config,
1039                                 "submodule.alternateLocation=superproject");
1040                         string_list_append(&option_config,
1041                                 "submodule.alternateErrorStrategy=die");
1042                 } else if (option_optional_reference.nr) {
1043                         string_list_append(&option_config,
1044                                 "submodule.alternateLocation=superproject");
1045                         string_list_append(&option_config,
1046                                 "submodule.alternateErrorStrategy=info");
1047                 }
1048         }
1049
1050         init_db(git_dir, real_git_dir, option_template, INIT_DB_QUIET);
1051
1052         if (real_git_dir)
1053                 git_dir = real_git_dir;
1054
1055         write_config(&option_config);
1056
1057         git_config(git_default_config, NULL);
1058
1059         if (option_bare) {
1060                 if (option_mirror)
1061                         src_ref_prefix = "refs/";
1062                 strbuf_addstr(&branch_top, src_ref_prefix);
1063
1064                 git_config_set("core.bare", "true");
1065         } else {
1066                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
1067         }
1068
1069         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
1070         strbuf_addf(&key, "remote.%s.url", option_origin);
1071         git_config_set(key.buf, repo);
1072         strbuf_reset(&key);
1073
1074         if (option_no_tags) {
1075                 strbuf_addf(&key, "remote.%s.tagOpt", option_origin);
1076                 git_config_set(key.buf, "--no-tags");
1077                 strbuf_reset(&key);
1078         }
1079
1080         if (option_required_reference.nr || option_optional_reference.nr)
1081                 setup_reference();
1082
1083         refspec_append(&rs, value.buf);
1084
1085         strbuf_reset(&value);
1086
1087         remote = remote_get(option_origin);
1088         transport = transport_get(remote, remote->url[0]);
1089         transport_set_verbosity(transport, option_verbosity, option_progress);
1090         transport->family = family;
1091
1092         path = get_repo_path(remote->url[0], &is_bundle);
1093         is_local = option_local != 0 && path && !is_bundle;
1094         if (is_local) {
1095                 if (option_depth)
1096                         warning(_("--depth is ignored in local clones; use file:// instead."));
1097                 if (option_since)
1098                         warning(_("--shallow-since is ignored in local clones; use file:// instead."));
1099                 if (option_not.nr)
1100                         warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
1101                 if (filter_options.choice)
1102                         warning(_("--filter is ignored in local clones; use file:// instead."));
1103                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1104                         if (option_local > 0)
1105                                 warning(_("source repository is shallow, ignoring --local"));
1106                         is_local = 0;
1107                 }
1108         }
1109         if (option_local > 0 && !is_local)
1110                 warning(_("--local is ignored"));
1111         transport->cloning = 1;
1112
1113         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1114
1115         if (option_depth)
1116                 transport_set_option(transport, TRANS_OPT_DEPTH,
1117                                      option_depth);
1118         if (option_since)
1119                 transport_set_option(transport, TRANS_OPT_DEEPEN_SINCE,
1120                                      option_since);
1121         if (option_not.nr)
1122                 transport_set_option(transport, TRANS_OPT_DEEPEN_NOT,
1123                                      (const char *)&option_not);
1124         if (option_single_branch)
1125                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1126
1127         if (option_upload_pack)
1128                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1129                                      option_upload_pack);
1130
1131         if (filter_options.choice) {
1132                 transport_set_option(transport, TRANS_OPT_LIST_OBJECTS_FILTER,
1133                                      filter_options.filter_spec);
1134                 transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
1135         }
1136
1137         if (transport->smart_options && !deepen && !filter_options.choice)
1138                 transport->smart_options->check_self_contained_and_connected = 1;
1139
1140
1141         argv_array_push(&ref_prefixes, "HEAD");
1142         refspec_ref_prefixes(&rs, &ref_prefixes);
1143         if (option_branch)
1144                 expand_ref_prefix(&ref_prefixes, option_branch);
1145         if (!option_no_tags)
1146                 argv_array_push(&ref_prefixes, "refs/tags/");
1147
1148         refs = transport_get_remote_refs(transport, &ref_prefixes);
1149
1150         if (refs) {
1151                 mapped_refs = wanted_peer_refs(refs, &rs.items[0]);
1152                 /*
1153                  * transport_get_remote_refs() may return refs with null sha-1
1154                  * in mapped_refs (see struct transport->get_refs_list
1155                  * comment). In that case we need fetch it early because
1156                  * remote_head code below relies on it.
1157                  *
1158                  * for normal clones, transport_get_remote_refs() should
1159                  * return reliable ref set, we can delay cloning until after
1160                  * remote HEAD check.
1161                  */
1162                 for (ref = refs; ref; ref = ref->next)
1163                         if (is_null_oid(&ref->old_oid)) {
1164                                 complete_refs_before_fetch = 0;
1165                                 break;
1166                         }
1167
1168                 if (!is_local && !complete_refs_before_fetch)
1169                         transport_fetch_refs(transport, mapped_refs);
1170
1171                 remote_head = find_ref_by_name(refs, "HEAD");
1172                 remote_head_points_at =
1173                         guess_remote_head(remote_head, mapped_refs, 0);
1174
1175                 if (option_branch) {
1176                         our_head_points_at =
1177                                 find_remote_branch(mapped_refs, option_branch);
1178
1179                         if (!our_head_points_at)
1180                                 die(_("Remote branch %s not found in upstream %s"),
1181                                     option_branch, option_origin);
1182                 }
1183                 else
1184                         our_head_points_at = remote_head_points_at;
1185         }
1186         else {
1187                 if (option_branch)
1188                         die(_("Remote branch %s not found in upstream %s"),
1189                                         option_branch, option_origin);
1190
1191                 warning(_("You appear to have cloned an empty repository."));
1192                 mapped_refs = NULL;
1193                 our_head_points_at = NULL;
1194                 remote_head_points_at = NULL;
1195                 remote_head = NULL;
1196                 option_no_checkout = 1;
1197                 if (!option_bare)
1198                         install_branch_config(0, "master", option_origin,
1199                                               "refs/heads/master");
1200         }
1201
1202         write_refspec_config(src_ref_prefix, our_head_points_at,
1203                         remote_head_points_at, &branch_top);
1204
1205         if (filter_options.choice)
1206                 partial_clone_register("origin", &filter_options);
1207
1208         if (is_local)
1209                 clone_local(path, git_dir);
1210         else if (refs && complete_refs_before_fetch)
1211                 transport_fetch_refs(transport, mapped_refs);
1212
1213         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1214                            branch_top.buf, reflog_msg.buf, transport,
1215                            !is_local);
1216
1217         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1218
1219         /*
1220          * We want to show progress for recursive submodule clones iff
1221          * we did so for the main clone. But only the transport knows
1222          * the final decision for this flag, so we need to rescue the value
1223          * before we free the transport.
1224          */
1225         submodule_progress = transport->progress;
1226
1227         transport_unlock_pack(transport);
1228         transport_disconnect(transport);
1229
1230         if (option_dissociate) {
1231                 close_all_packs(the_repository->objects);
1232                 dissociate_from_references();
1233         }
1234
1235         junk_mode = JUNK_LEAVE_REPO;
1236         fetch_if_missing = 1;
1237         err = checkout(submodule_progress);
1238
1239         strbuf_release(&reflog_msg);
1240         strbuf_release(&branch_top);
1241         strbuf_release(&key);
1242         strbuf_release(&value);
1243         junk_mode = JUNK_LEAVE_ALL;
1244
1245         refspec_clear(&rs);
1246         argv_array_clear(&ref_prefixes);
1247         return err;
1248 }